Retrofit Window Replacement

Installing Into the Opening You Already Have

A retrofit window has a flange around its perimeter that laps over the face of the stucco. The old sash and glass come out, the old frame stays in the wall, and the new unit is set into it and sealed at the flange. No stucco is cut. No lath is disturbed. Interior casing and drywall are untouched.

On a sound opening this is a genuinely good detail, and it is what most Riverside tract houses from the nineteen seventies through the nineties get. It is faster, it costs less than half of a full frame job, and it leaves nothing to repaint inside.

The Condition That Has to Be True First

The retrofit flange and its sealant joint become the outermost water barrier at that opening. Everything behind them is whatever the original crew built, and you are not changing it.

So the whole question is whether what is behind is dry and sound. We check that before quoting, not after. That means looking at the reveal, probing the sill for softness, checking the stucco below the opening for the tell tale efflorescence line, and where there is any doubt, opening a small area at a lower corner.

If it comes back dry, retrofit is the right answer and we will say so plainly. If it comes back wet, a retrofit is the wrong tool, because a new flange over a wet opening seals the evidence in and slows the drying rather than stopping the water.

How We Detail the Joint

The flange gets bedded, not just caulked afterward. Sealant goes on the back of the flange before the unit is set, so the bond is between the flange and the stucco face rather than sitting in a bead on top of it where sun and movement get at it directly.

The perimeter joint is then tooled, not left as an extruded bead. A tooled joint has contact on both faces and a concave profile that lets it stretch. This matters more here than in most places, because a west facing Riverside elevation puts a joint through a large daily temperature swing for months at a time and a joint that was only smeared on will let go within a few seasons.

We leave the sill weeps clear. This sounds obvious and it is one of the most common things we find caulked shut by a previous crew. A window frame is designed to drain internally to those weeps. Seal them and the frame fills.

Frame Choice in This Climate

Vinyl is the default and it is fine, but the heat matters. A dark vinyl frame on a south or west elevation runs hot enough to move noticeably, and cheap extrusions with thin walls and few chambers will show it at the corners within several years. We specify frames with welded corners and reinforcement in the larger sizes.

Fiberglass costs more and moves much less with temperature, which on a long horizontal slider on a west wall is worth the difference. On a shaded north elevation it usually is not, and we will tell you that rather than upselling the whole house.

What You Lose

Retrofit costs you glass area. The new frame sits inside the old one, so every opening gets slightly smaller, typically an inch or so around. On a large picture window nobody notices. On a small bathroom window it is visible, and on a house where only some windows are being done it can leave a mismatch between rooms.

You also keep the original sill condition, whatever it is. No pan is added. That is not a defect in the method, it is the trade you are making, and it is the reason we insist on checking the opening first.

Call (951) 632-2842 and we will look at what you have before anyone quotes a number.